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/* ipv4.h */
/*
* Routines for dissecting IPv4 and UDP packets.
*
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is the MPEG TS, PS and ES tools.
*
* The Initial Developer of the Original Code is Amino Communications Ltd.
* Portions created by the Initial Developer are Copyright (C) 2008
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Richard Watts, Kynesim <rrw@kynesim.co.uk>
*
* ***** END LICENSE BLOCK *****
*/
#ifndef _ipv4_h
#define _ipv4_h
#include "compat.h"
/*! This is all held in host byte order (including the
* IP addresses! You have been warned .. )
*/
typedef struct ipv4_header_s
{
// IP version. Should really be 4 :-)
uint8_t version;
// Header length.
uint8_t hdr_length;
// Type of service.
uint8_t serv_type;
//! Total length
uint16_t length;
//! Ident
uint16_t ident;
//! Flags
uint8_t flags;
//! Frag offset.
uint16_t frag_offset;
//! TTL
uint8_t ttl;
//! Protocol (typically UDP or TCP)
uint8_t proto;
//! Header checksum (we don't check this!)
uint16_t csum;
//! Source address.
uint32_t src_addr;
//! Destination address.
uint32_t dest_addr;
//! We don't track options.
} ipv4_header_t;
// Is this header UDP?
#define IPV4_HDR_IS_UDP(h) ((h)->proto == 17)
#define IPV4_ERR_PKT_TOO_SHORT (-1)
/*!
* Unwrap ipv4.
*
* \param out_st OUT Index into data at which IPv4 payload starts.
* \param out_len OUT Length of the IPv4 payload.
* \return 0 on success, -1 on failure.
*/
int ipv4_from_payload(const uint8_t *data,
const uint32_t len,
ipv4_header_t *out_hdr,
uint32_t *out_st,
uint32_t *out_len);
typedef struct ipv4_udp_header_s
{
//! Source port.
uint16_t source_port;
//! Dest port.
uint16_t dest_port;
//! Length (yes, yet another one!)
uint16_t length;
//! Checksum
uint16_t csum;
} ipv4_udp_header_t;
/*!
* Unwrap UDP.
*
*/
int ipv4_udp_from_payload(const uint8_t *data,
const uint32_t len,
ipv4_udp_header_t *out_hdr,
uint32_t *out_st,
uint32_t *out_len);
#endif
/* End file */
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